Gun



Feb. 29, 1944.

W. SUMMERBELL GUN Filed July 13, 1939 2 Sheets-Sheet 1 Wi 1 1. .um E ummav'tlall Feb. 29, 1944. w. suMMERBELL. 2,342,705

GUNV

Filed July 13. `11.939 2 Sheets-Sheet 2 Fig 5- Figi lnvevtmv W'il L itu-r1 Eummav'hall Eby @mdd 'Attinna 5 Patented Feb. 29, 1944 UNl'i'D ST'i' asians vS PATENT OFFICE (Granted under-.the act of March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) 12 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, Without the payment to me of any royalty thereon.

rhis invention relates to a gun.

The purpose of the invention is to provide a gun in Which the recoil and counterrecoil mechanism for a breech block of the blow-back type is mounted on the gun barrel forwardly of the gun frame and is associated with a buffer having provision for readily coupling and uncoupling these elements.

Other objects are to provide a gun frame which is conveniently formed of a tube and to provide a novel means for coupling and locking the gun frame and gun barrel. f

'T he specific nature of the invention as wel as other objects and advantages thereof Will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

Fig. 1 is a plan view with parts removed and parts in section of the rear end of a gun constructed in accordance with the invention.

Fig. 2 is a View in side elevation with parts removed and parts in section.

Fig. 3 is an enlarged sectional view through the latch which locks the barrel and casing.

Fig. 4 is an enlarged sectional view on the line .-4 of Fig. 2.

Fig. 5 is a plan view partly in section of the buffer mechanism.

Fig. 6 is a View in side elevation of Fig. 5 with parts in section.

Figure '7 is a View like Figure 5 showing the unlatched position of the buifer mechanism.

Referring to the drawings by characters of reference the gun frame comprises a cylindrical casing A which is a length of seamless tubing. The front part of the casing receives a portion of a tubular gun barrel B while the rear part receives a non-circular reciprocating breech block C. In order to guide the breech block the casing A has opposite portions of its cylindrical wall removed and replaced by parallel plates 5--5 which are secured in any suitable manner, specically by welding. The plates are formed with inwardly disposed longitudinally extending rails 5 6 tting in correspondingly arranged recesses 'I in the breech block to establish a guide for the reciprocable block.

The front cylindrical part of the casing is formed with longitudinally spaced bearings 8 and 9 so that the enclosed portion of the barrel is ilutes Hl over the greater portion of its length to vfacilitate cooling and these flutes extend partly through the forward bearing 8. The-breech end .of the barrel is Vprovided externally with a plurality oi locking lugs II which are adapted, upon angularly displacing the barrel, to engage corresponding locking lugs I2 provided internally in the casing in rear `of the rear bearing 9. The locking relation of the gun barrel and casing is maintained by means of a latch I3 which is mounted in a housing I4 secured to the casing. The latch includes a pair `of longitudinally spaced keys I-i 5 which, when the latch is moved rearwardly by its spring I6, are normally disposed in kcyways Il in the locking vlugs II on the barrel. When the latch is moved forwardly against the action of spring I6 the keys enter .keyways Hain the locking lugs I2 ofthe casing and thereby permit relative rotational movement between the barrel and casing to disconnect the locking ugs.

The bearings 8 and 9 are each formed with oppositely disposed grooves or recesses IB forreceiving a pair of bars i-IS whose rearextrernie ties are each formed with lugs 20 for engaging corresponding lugs 2| on the Vsides of the breech block. The bars extend forwardly from-the cas.. ing in spaced relation to the gun barrel and are integral with a short cylindrical sleeve 22 (Fig. 5). A second sleeve 23-threadedly secured to the sleeve 22 internally carries a nut 2A which is provided at its rear end with a collar 25 disposed in a recess in the sleeve.2,3 and conned between the end of sleeve v22 and `a shoulder 26 of sleeve 23. The lnut extends forwardly beyond the sleeve 23 and the projecting portion is provided with aperturesl whereby it may be engaged by a tool and be rotated in place.

The nut is internally threaded to engage a spring seat 28 which slidably embraces thergun barrel. 'A pin 29 .Carried by the spring seat projects inwardly `and rides in a'flute lil of the gun barrel so that it serves to constrain the `spring seat to a reciprocable movement Whenthe nut is rotated to vary the adjustment of the spring.

A helical spring 30 preferably of square section, surrounds the gun ybarrel and is coni-ined between the seat 2.8 and the annular shoulder I of the barrel at the forward end of the casing A.

A pair of telescoping sleeves -comprisinga rear sleeve S2 and `a frontsleever are mounted on the gun barrel forwardly'of the spring @il and are interconnected through a bayonet jointll.

amply supported. The barrel is formed with The vsleeves andz33rare provided at their outer ends with collars, respectively and 38 which constitute seats for a buffer spring 31. The front collar 36 is supported against forward movement by a plate 38 which is threadedly xed to the gun barrel and secured in any approved manner while the rear collar 35 is in engagement with the flutes I of the barrel.` The front sleeve 33 includes a pair of rearwardly extending guide fingers 39-39 which pass through apertures in the rear collar 35.

The front collar 35 is provided with oppositely arranged pairs of spaced arms 40-40 extending rearwardly exteriorly of the buffer spring and terminating approximately midway thereof. A

pivot pin 4| in the extremities of each Vpairof arms carries a lever 42. A hook 43 on the rear end of each lever is adapted to catch a hook 44 i on the sleeve 23. The hooks are provided with cooperating cam faces 43a and 44a.

The front arm of each lever extends through an aperture 45 in the plate 38 and is normally held against the outer side wall dening the aperture by a spring 45. In this position the hooks 43 and 44 are in engagement. The front extremity of the lever is formed with an outwardly curved end 41 which constitutes a cam and is adapted, on retraction of the lever, to engage the plate 38 and rotate the lever to disengage the hooks.

The breech block C is of the blow-back type shown in Patent No. 1,144,285 of June 22, 1915, and it is not locked in battery for firing. In operation, the initial loading of a round of ammunition into the gun barrel is accomplished by retracting the breech block in any suitable manner and then releasing it. On the return stroke thebreech block strips a round from the maga- Zine (not shown) and advances it into the chamber of the gun barrel. As described in detail in the above -mentioned patent the round is red before the breech block arrives in battery so that the gas pressure is first utilized to arrest the forward motion of the breech block before acting to drive it rearwardly in recoil. This pressure buis and stops the breech block before it reaches the rear face of the gun barrel andthe explosive energy of the gases does not react with its full force on the breech block in driving it rearwardly.

During retraction or recoil of the breech block the bars I9 and sleeves 22--23 serve to compress the spring 38, which action checks the recoiling movement of the block and provides the energy for moving the block in countercoil.

As shown in Figs. 5 and 6 when the parts are at rest the hooks 43 of the buffer mechanism and the hooks 44 of the breech block mechanism are in engagement. During the initial retraction of the breech block the levers 42 are likewise retracted by virtue of the engagement of the hooks and the front collar 38 which carries the levers is moved rearwardly to compress the buffer spring 31 against the barre1 through the rear collar 35. After a short travel the 1evers 42 are rocked by engagement of the end 41 with the support plate 38 and are disconnected from the hooks 44 on the sleeve 23, and following this operation the front collar 38 is restored to its normal position against the support plate In the instance where the round is red before the breech block arrives in battery, the hooks 44 do not move forward sufficiently to engage the hooks 43. In the event of a hangre or misrire the breech block goes fully home and the nut 24 strikes the collar 35 which moves forward to compress the buier spring 31. The buffer spring checks the velocity of the counterrecoiling breech block and eases it into battery. As fthe breech block moves forwardly the additional distance into battery the hooks 44 engage the hooks 43.

In the event of a msre the levers 42 may be manually rotated to disconnect the buier mechanism. In the event of a hangfire the maximum energy of the powder gases is available to Ydrive the breech block rearwardly but because of the connection between the hooks 43 and 44 the buffer spring is initially utilized to counteract the energy of the powder gases.

The casing A carries a band 48 which includes trunnions 49 for mounting the gun on a support or carriage.

. I claim:

1. In a gun, a casing, a barrel connected to the casing, a blow-back breech block slidably mounted in the casing in rear of the barrel, bars connected to the breech block and extending forwardly through the casing and alongside the barrel, a sleeve fixed to the front extremities of the bars, an end sleeve attached to the sleeve on the bars, a rotatable nut within the end sleeve and having a collar confined between the sleeves, a spring seat threaded in the nut, means for constraining the spring seat to reciprocal movement on rotation of the nut, and a spring surrounding the gun barre1 and confined between the seat and the rear portion of the gun barrel.

2. In a gun, a barrel, a pair of telescoping sleeves on the barrel and having a bayonet joint connection, a collar on each sleeve, a buffer spring between the collars, means for limiting movement of the sleeves under action of the spring, oppositely arranged pairs of spaced arms extending rearwardly from the foremost collar, a lever pivotally mounted in each pair of arms and having a hook on its rear end, the front end of each lever engageable with a xed element. of the barre1 on retraction of the lever to cause rocking of the lever, a blow-back breech block in rear of the barrel, a recoil and counterrecoil mechanism for the block engageable with the rearmost sleeve on the barrel, and hooks on said mechanism engageable with the hooks on the levers.

3. In a gun, a fixed barrel, a buffer mechanism on the barrel comprising spaced movable collars, a buifer spring between the collars, means on the barrel for limiting movement of the collars under action of the spring, a pair 0f levers pivotally carriedby the foremost collar, a blow-back breech block in rear of the barrel, a recoil and counterrecoil mechanism for the block engageable with the rearmost collar of the buffer mechanism, means on said mechanism for coupling it to the levers for joint retraction therewith, and means for uncoupling the levers from said preceding meansafter a predetermined joint retraction.

4. In a gun, a fixed barrel, a buffer mechanism on the barrel comprising spaced collars each movable with respect to the other and to the barre1, resilient buffer means between the collars, means on the barre1 for limiting divergence of the collars under action of the resilient means, a blow-back breech block in rear of the barrel, a recoil and counterrecoil mechanism for the block engageable with the rearmost collar of the buffer mechanism, means on said mechanism for coupling it to the foremost collar of the buffer mechanism for joint retraction therewith, and means for uncoupling said members after a predetermined joint retraction.

5. In a gun, a frame comprising a cylindrical casing having a front portion for receiving a gun barrel and a rear portion for receiving a breech block, the rear portion of the casing having opposite sides cut away, a pair of parallel plates Xed in the cut-away sides of the casing and having guides, a breech block Slidably mounted in the rear portion of the casing between the parallel plates and engaging the guides of the plates and means on the casing approximately midway of its length for engaging a gun barrel.

6. In a gun, a, frame comprising a cylindrical casing having a front portion for receiving a gun barrel and a rear portion for receiving a breech block, the rear portion of the casing having opposite sides cut away, a pair of parallel plates xed in the cut-away sides of the casing, a breech block slidably mounted in the rear portion of the casing between the parallel plates and means on the casing approximately midway of its length for engaging a, gun barrel.

7. In a gun, a fixed barrel, a buier mechanism on the barrel comprising spaced collars disposed around the barrel each movable with respect to the other and to the barrel, resilient buffer means between the collars, means on the barrel for limiting divergence of the collars under action of the resilient means, a blow back breech block in rear of the barrel, and a member on the block engageable with the rearmost collar of the buier mechanism only when the block is in full battery.

8. In a gun, a barrel, a blow back breech block adapted to insert a cartridge in said barrel, means associated with said breech block for firing the cartridge before the breech block reaches full battery position, whereby the counterrecoil motion of the breech block is arrested by the gas pressure from the cartridge before the breech block reaches the rear face of the barrel, an extension on the breech block extending forward thereof, spring seat means on said extension, a shoulder on said barrel and a counterrecoil spring between' said seat means and said shoulder, a. buier spring forward of said extension and positioned to be compressed thereby when the breech block is advanced beyond the normal limit of counterrecoil, means forward of said buffer springengageable with said extension on abnormal advance of the breech block to hinder recoil by compression of the buffer spring, and means for automatically releasing said engageable means after a definite travel of the breech block in decelerated recoil.

9. In a gun, a barrel, a blow back breech block adapted to insert a cartridge in said barrel, means associated with said breech block for iiring the cartridge before the breech block reaches full battery position, whereby the counterrecoil motion of the breech block is arrested by the gas pressure from the cartridge before the breech block reaches. the rear face of the barrel, stop means on the barrel, a buffer spring freely compressible inward from said stop means, a member on the breech block aligned with the buffer spring, said spring being positioned out of reach of said member in the normal limit of counterrecoil of the breech block but compressible by said member when the latter moves beyond said normal limit, and means on the forward portion of said buifer spring engageable by said member for retraction therewith on recoil.

10. In a gun as in claim 9, means for automatically releasing the member of the breech block from the means on the forward portion of the buer spring after a predetermined distance of recoil of the breech block.

11. In a gun, a barrel, a breech block adapted to insert a cartridge in said barrel, means associated with said breech block for iiring the cartridge before the breech block reaches full battery position, whereby the counterrecoil motion of the breech block is arrested by the gas pressure from' the cartridge before the breech block reaches the rear face of the barrel, a pair of stop means on the barrel, buffer means compressible inward from both the stop means on the barrel and positioned out of the normal forward limit of advance of said block but within the path of said block when the latter moves beyond said forward limit, and means engageable with the forward end of said buffer means and adapted to be connected with a portion of said block when advanced beyond said normal forward limit to decelerate recoil of said block by compression of said buffer means.

12. The invention of claim 11 characterized in that there is means for automatically releasing the forward end of the buffer means from the breech block after deceleration.

WILLIAM SUMMERBELL. 

